Militants' storming of a Pakistani Air Force base where some nuclear warheads are reportedly stored has once again sounded the alarms about the security of the country's atomic weapons.

Minhas air base, located just 40 kilometers west of Islamabad in the eastern Punjab Province, is considered a key military facility. It houses warplanes and some of Pakistan's most advanced weapons systems -- possibly including nuclear warheads.

So the August 16 attack that left nine suspected Islamic radicals and one Pakistani soldier dead once again raised eyebrows over Islamabad's claims that its nuclear installations are under foolproof security.

Much of the concern is predictable, but misdirected, according to experts.

The location of Pakistan's nuclear weapons are a highly guarded secret, but despite news reports to the contrary, most observers doubt that warheads are stored at Minhas.

Retired General Talat Masood says the real concern is the increasing frequency of high-profile attacks on military facilities.

"When defense installations are being targeted so easily -- and we have seen a series of events taking place, starting from the [military's General Headquarters] GHQ to the Mehran [Naval] base, and now this Air Force base -- it shows that these places are vulnerable and Pakistan will have to do a lot more," Masood said.

Embarrassing Breaches

The country's military, which controls the nuclear arsenal, has suffered numerous embarrassing attacks on key bases in recent years.

In May 2011, at least two naval surveillance aircraft were destroyed and 10 people were killed when militants stored the Mehran naval bases in the southern seaport city of Karachi. In October 2009, militants stormed the headquarters of the Pakistani military in Rawalipini close to Islamabad. They took scores of hostages, who were freed after nine attackers were killed in a nearly 20-hour gun battle.

Retired Pakistani Brigadier-General Asad Munir, who formerly served in the senior ranks of the military's Inter-Services Intelligence Agency, says that all nuclear installations -- whether civilian or military -- are guarded with elaborate security arrangements.

He says that Western countries' concerns that nuclear weapons could fall into the wrong hands have been put to rest.

"They know it. They have been here, they have seen the system. They know that it is not easy. It is almost impossible [to breach the nuclear security]. Otherwise they would have taken action. The people who matter know that nobody is in a position to take these installations and take away nukes," Munir said.

The UN's nuclear watchdog, the International Atomic Energy Agency, considers Pakistan's nuclear program safe and secure.

Islamabad has established an elaborate nuclear security apparatus called the Strategic Plans Division. It reportedly keeps the fissile core of Pakistan's nuclear warheads separate from their delivery systems.

Islamabad has received some $100 million in U.S. assistance since 9/11 to improve its nuclear safety. Pakistan has reportedly developed its own technologies to prevent accidents and to implement an elaborate system of checks and balances.

And as Munir notes, those measures are backed by a strong human deterrent.

"As long as the Pakistani army is there, there is no threat to the nuclear weapons. Not even 1 percent," Munir said.